Jessica Simpson called off her relationship with John Mayer over his 'embarrassing' comments

Singer Jessica Simpson has opened up about her turbulent relationship with ex-boyfriend John Mayer in her memoir, revealing she walked out of it after Mayer called her a "sexual napalm" in an interview.

The comments, Simpson said, broke her trust in Mayer.

In the memoir, "Open Book", Simpson said she met Mayer at a party in 2005 when she is finalising her divorce from Nick Lachey. After that, the two quickly became involved.

"He'd walk into a room and pick up his guitar and you'd swoon. I didn't really know the man behind the guitar. And that was my mission," the 39-year-old singer told People magazine.

In the book, Simpson wrote that Mayer used to regularly tell her that he was "obsessed with me, sexually and emotionally".

The singer further said she would often feel insecure around Mayer, 42, because she thought she wasn't "smart enough" for him.

"I constantly worried that I wasn't smart enough for him. He was so clever and treated conversation like a friendly competition that he had to win," Simpson said.

The relationship would often cause her anxiety to "spike and I would pour another drink. It was the start of me relying on alcohol to mask my nerves."